We use gears in so many aspects of our lives and may not even realize the importance these tiny parts play in our life. They’ve been around for centuries–in fact, gears are one of the oldest tools that transfer motion. A gear (also known as a cogwheel) is a circular piece of metal that has teeth. When put together with another gear or machinery part, it transmits torque. While you can buy generic gears at any hardware store, some gear manufacturers offer custom made gears for special projects or machines. However, regular gears come in a wide range of shapes and sizes: bevel gears, spur gears, and worm gears are some examples of the most common types.
What Kind of Gears are There?
There are many types of gears that all play different functions. One of the reasons gears are so heavily relied on is because their teeth eliminate slippage. One of the most basic types of gear come in the form of external and internal gears. An external gear can be defined as a gear that has teeth on the outside (or external) part of the circle. An internal gear, then, has teeth on the inside surface of the circle. Other types of gear include worm gears, bevel gears, hypoid gears, spur gears, and rack and pinion gears.
A More In-Depth Look at Other Types of Gears
Worm gears resemble the shape of a screw and is typically used in conjunction with a helical gear (also known as a spur gear). Worm and gear sets are a great and easy way to achieve high torque. Its popularity is due to its function as a large gear reductor. In this function, the worm can usually turn the gear, but not the other way around. This creates friction that keeps the worm in place. This friction can often act as a brake and are usually used with a spur gear. Some places worm gears can be found are in hoists, car steering mechanisms, and conveyor belts.
Bevel gears have a shape that resembles a right circular cone. They are typically used on shafts set at a 90 degree angle. Bevel gears are popular because of its versatility; it allows you change the operating angle. Bevel gears are typically found in one of two categories: the straight bevel gear or the spiral bevel gear. In the straight bevel gear, the teeth of the gear are straight and run parallel to the pitch surface of the bevel gear. In the spiral bevel gear, the teeth are curved and set at an angle. The curve and angle allows the spiral bevel gear to operate with less vibration and noise than the straight bevel gear. Some places you can find bevel gears are in power plants, painting presses, cars, and trains.
What Materials are Popular for Gears?
Cast iron is popular for gears, especially bevel gears because of its durability. Steel and other alloys are also popular. When looking at custom made gears, usually one of the most important parts of designing is choosing the material to use, such as stainless steel, plastic, or nylon. Many manufacturers of custom made gears will have some sort of design software where you can choose your materials and design your gear.